15. Handy Instruction Design Examples 15.6 FTC - Fuzzy Temperature Control of the Oven Control Purpose: z The heating environment of the oven is “fast heating environment” (D13 = K16) and the target temperature is 120 ℃ (D10 = K1200). In order to get the best control results, the program uses FTC together with GPWM instructions to perform fuzzy temperature control. z Apply DVP04PT-S temperature measurement module for measuring the present temperature of the oven and transferring the result to DVP12SA. After execution of FTC instruction, PLC outputs the operation results in D22 to the input of GPWM instruction.
GPWM instruction outputs width modulatable pulses (width determined by D22) by Y0 to control the heater and fuzzy temperature control of the oven is completed. D22 Y0 D30 Devices: Control Program: M1002 Set target temperature:120 ℃ Set the average time of Channel 1: 2 times DVP04PT Set sampling time: 4s Set the heating environment to "fast heating environment Set the pulse output cycle of GPWM:
4s Execute FTC and GPWM instructions DVP-PLC Application Examples 15-18 Device Function M1 Enabling the execution of FTC instruction Y0 PWM Pulse output device D10 Storing the target temperature D11 Storing the present temperature D12 Storing FTC sampling time parameter D13 Storing FTC temperature control parameter D22 Storing the operation results of FTC instruction D30 Storing the pulse output cycle of GPWM instruction MOV K1200 D10 TO K0 K2 K2 K1 MOV K40 D12 MOV K16 D13 MOV K4000 D30 SET M1